error-handlingexceptiongrakotatsu

How to get concise syntax error messages from grako/TatSu

If the input to a grako/tatsu generated parser has a syntax error, such as 3 + / 3 to the calc.py examples, one gets a long list of Python calling sequences in addition to the relevant 3 + / 3 ^ I could use try - except constructions but then I lose the relevant part of the error message as well.

I would like to use grako/tatsu to parse grammar rules for a rule compiler and I appreciate the possibility of separating the syntax and semantics in a clean way. The users would be quite annoyed of the excessive error messages. Is there a way for clean error messages?

Solution

  • This should be the same as in any Python program. If you let the exception escape main(), then a stack trace will be printed. Instead, you can write:

    try:
   do_parse()
except Exception as e:
  print(str(e))